1. Field of the Invention
This invention relates to a laminated structure. More particularly, this invention relates to a laminated structure comprising a metal-polybutylene structure with a functionalized block copolymer tie layer.
2. Prior Art
Laminated structures comprising a plurality of polymeric layers are, of course, well known in the prior art. Such structures are taught in U.S. Pat. Nos. 4,058,647; 4,198,327; 4,332,858; 4,341,837 and 4,588,648 and in Japanese Patent Application No. Sho 58[1983]-13242. U.S. Pat. Nos. 4,332,858 and 4,341,837 teach that various polymeric materials including olefin homopolymers, olefin copolymers such as ethylene and vinyl alcohol, polycarbonates and the like may be adhered with a modified, but unhydrogenated, block copolymer such as a maleated block copolymer of styrene and butadiene. U.S. Pat. No. 4,588,648 teaches that certain polymeric materials such as polypropylene and ethylene/vinyl alcohol copolymers may be laminated with an adhesive layer comprising a grafted copolymer of an olefin and maleic anhydride and an ungrafted polypropylene. However, none of these references describe or suggest a method for bonding polybutylene to metal.
Adhesive and similar compositions which may, at least, comprise a hydrogenated block copolymer containing at least one monoalkenyl aromatic hydrocarbon block and at least one conjugated diolefin block, are, of course, known in the prior art. Polymeric compositions which may contain a hydrogenated block copolymer are taught, for example, in U.S. Pat. Nos. 3,607,977 and 3,970,711 and in European Patent Application No. 0169987. U.S. Pat. No. 3,607,977 teaches compositions comprising a block copolymer containing at least two monoalkenyl aromatic hydrocarbon polymer block and a block copolymer comprising at least one monoalkenyl aromatic hydrocarbon polymer block and at least 10% of the initial unsaturation is reacted so as to incorporate a polar group. The block copolymers may, independently, be neat or hydrogenated. The polar group may be an oxygen containing group such as a carboxyl group. Compositions comprising an oxygen containing group are said to be especially useful as adhesives, particularly for polar textile such as cellulose. However, there is no indication that these adhesives would be useful for the preparation of polymer laminates comprising metal and polybutylene layers. The problem of bonding polybutylene to metal substrates has been a problem for many years. There is therefore a need for laminated structures, comprising a metal and polybutylene.